We have a large range of competitively priced braked and unbraked Axles from brands including Knott, BPW & AL-KO.
What is a braked trailer axle?
A braked Axle is equipped with a braking system. In most cases, this is the traditional drum brake. There are also Axles with a hydraulic braking system or disc brakes. But as these systems are much more expensive than drum brakes and often also require modifications to the towing vehicle, they are not widely used in the assembly of new trailers.
When braking, the overrun brake and brake cable system depresses the overrun brake, causing the brake cables to tighten the brake shoes against the brake drum, thus braking the Trailer itself. If the pressure then decreases again on the overrun brake, the brake shoes will also release their grip on the drum. A braked Axle is therefore equipped with a Brake drum with the corresponding brake shoes already fitted. The Axle also always comes with the corresponding Wheel bolts.
What is an unbraked trailer Axle?
An unbraked trailer axle is an axle with Bearings but without a drum brake. The braking action must come entirely from the towing vehicle. This is also why the maximum gross loading capacity of an unbraked trailer often does not exceed 750 kg to max 1050 kg, otherwise the load on the towing vehicle is too great. What is allowed depends on the vehicle and is stated in the registration certificate. There are also unbraked Axles with waterproof Bearings. This is especially useful if you have a boat trailer that often drives into the water.
What should you pay attention to when replacing your Trailer's torque Axle?
First of all, it is important to know why you want to replace the Axle. Is the swing arm crooked or do the axle rubbers need replacing? Always choose the same brand of Axle as what is already under it to ensure brake operation.
How can you tell if the swing arm is warped?
You can easily see this when you remove wheels from the Axle. It is then important to measure the angle of the Axle as shown schematically in the picture below. If the angle is less than 20 degrees, the Axle is warped. Replacing it is then a better and often cheaper solution than repairing it.
Are you going to replace the trailer Axle? Then there are a few important technical terms you need to understand to know which Axle you need.
What is a torsion axle?
A torsion axle is the most commonly used axle by trailer manufacturers and means nothing more than a rubber sprung axle. The suspension is in the axle housing itself. Another variant is, for example, leaf suspension. You still see these a lot in the UK. A torsion axle can be recognised by the arm that attaches the tube profile of the axle to the Brake drum. Here you will find our range of torsion Axles.
What is the pad size of a trailer?
The path size is the distance of the centre-to-centre distance of the Axle's fixing holes. See the drawing below. The pad size is the most important dimension for the Axle if you want to replace it.
What is the track width of an Axle?
The track width is the intermediate distance to the centre of both tyres. Depending on the ET value, the Rim determines whether it sits more inward or outward.
What is the flange size of an Axle?
Besides the pad size, the flange size is also important. Often this is a standard dimension from the pad size ( 450mm) but not always. So to make sure you order the right Axle, measure = know! The flange size is the distance between the two outer sides of the brake drum. Measured from the flat outside, so without Wheel bolts and Hub caps!
When will my Trailer Axle be delivered?
Most Axles can be delivered from stock and are therefore delivered to the desired address within three working days. For less common and custom-made Axles, delivery times vary. Please contact our customer service team for exact delivery times.
What do you need to consider when replacing the Trailer Axle?
If you are going to replace the Axle, it is always important that you do this with the same brand of Axle as was already fitted. Because the overrun brake, brake cables and drum brake are an interplay of elements that is described in the braking diagram on which the trailer is approved for use in Europe.
Axles always state the pad size and flange size. What exactly is this? The path size determines the distance between the Axle's fixing holes on the chassis. So centre-to-centre is the distance of the fixing holes. The flange size is the distance between the two outer sides of the drum. So this is the outside on which the Rims are mounted.
We can supply almost all sizes of Axles. Before ordering an Axle, it is important to know the PAD and FLENS size. You also need to know in advance which pitch size you need. Read here how to measure pad, flange and pitch dimensions.
A wide choice of load capacities for trailer axles
It is also important to know the required load capacity of the Axle. Normally, you will find this information on the axle's rating plate. Load capacities of trailer axles vary between 750 and 1800 kg.
Personal advice on selecting the right Axle
If, after reading the above information, you still cannot find the right Axle, please contact our customer service team, who will be happy to help you.
Used Trailer Axles
We recommend not buying second-hand Axles, as they are often damaged. It is better to buy new Axles, which are generally only slightly more expensive than second-hand Axles. The advantage of a new Axle is that you have a warranty on it and can be sure that everything will work properly.
Axle repair of Trailer
When it is possible to repair an Axle, these costs are often as high as those of replacing the complete Axle for the Trailer. Due to the high turnover rate, we can offer Axles from KNOTT and BPW very cheaply. So you get a premium brand Axle delivered directly from stock at a competitive price.
When an Axle is bent and straightened, the quality of this Axle decreases. This is why we always recommend a new Axle, especially if it is bent.
More information about trailer torsion Axles
Nowadays, almost all trailers are fitted with torsion Axles. This used to be different, when Axles were fitted with leaf springs in most cases. Torsion Axles are significantly better than leaf-sprung Axles. Torsion Axles have better roadholding, resulting in better handling.
The simple design of torsion Axles makes them more durable, cheaper and easier to maintain than other types of Axles.
How does a trailer torsion axle work?
A torsion is is made of an Axle with wishbones in both ends. These wishbones are sandwiched all around by 3 or 4 rubber strands. When the support arm of a torsion axle is put under pressure it is absorbed by the rubber strands in the axle itself, as soon as this pressure drops again the rubber in the axle will expand and the wheel will return to its original position. This is a simple but hugely durable concept.
Which Trailer Axle do I need?
In this video, we showed what determines the size of an Axle, how to know the size of a Brake drum and which Brake shoes are applicable for it.
80% of all Axles are produced by two manufacturers, Knott and AL-KO. Until last year, BPW was also a player but it was taken over by AL-KO. No BPW Axles have been produced since then.
Brake drums are located on the outside of the Axle. These often have 4 holes (pitch 4x100 (almost all unbraked Axles)) or 5 holes (braked Axles) to which the Rims are mounted with Wheel bolts. Brake drums are measured by determining the inner diameter of the drum. If you know the inner diameter and the width/depth of the drum, you also know which brake shoes will fit.
Always use the same brand of drum and brake shoes as the Axle. You can choose original brand parts or replica parts. There is no compulsory MOT inspection for trailers and caravans so it is the user who is responsible for proper operation. In fact, if an accident shows that the material was not OK, this can have a nasty criminal aftermath. So outsource this to the professional or do it yourself and make use of YouTube instruction videos that we also make.